PARASITIC COPEPODA. 201 



terminal one armed with four spines on the outer margin and three rowing setae on 

 the inner. 



The second, third and fourth swimming legs are as in other Euryphorinse and the 

 Trebinae, particularly in the form of the second joint of the endopod and in the 

 number and arrangement of the spines and setae. The following table represents 

 the arrangement of spines and setae on each joint : 



Second legs, exopod . . . 2-1, 1-1, 1-5. 



endopod . . . 0-1, 0-2, 0-6. 



Third legs, exopod . . . 1->1, 1-1, 3-5. 



endopod . . . 0-1, 0-2, 1-4. 



Fourth legs, exopod . . . 1-1, 1-1, 3-5. 



endopod . . . 0-1, 0-2, 1-3. 



The fifth legs appear as small papillae at the posterior corners of the genital 

 segment, each armed with three setae. 



Of the reproductive organs the cement glands are rather small, broadly club- 

 shaped, and they reach but little in front of the centre of the genital segment. The 

 component cells are of medium size and there are about twelve in each gland. The 

 semen receptacle is very close to the posterior margin ; it is considerably curved, with 

 the concave side directed forwards. The ends are slightly enlarged and from each a 

 duct runs forward and empties into the oviduct anterior to the opening of the cement 

 gland. 



Colour of preserved specimens a uniform yellowish white without pigment spots 

 or lines. 



Total length 3 millims., length of carapace 0'85 millim., width of same l*75millims., 

 length of free thorax 1*1 millims., length of genital segment 0'71 millim., of abdomen 

 0'34 millim., of egg-strings 2*35 millims. 



Male. Similar to the female in general appearance and in most of the details of 

 structure. Carapace transversely semilunar, a little more than twice as wide as long. 

 Second, third and fourth thorax segments diminishing slightly in width, but increasing 

 in length, the fourth segment nearly one-half longer than the second. Second 

 segment the only one furnished with lateral plates, but the large basal joints of the 

 third and fourth legs have all the appearance of lateral plates in dorsal view, as in 

 the female. 



Genital segment elongate-spindle-shaped, one-third longer than Made, with evenly 

 rounded sides ; the anterior margin re-entrant, the posterior one nearly squarely 

 truncated. Two pairs of rudimentary legs are visible, one pair on the lateral margin 

 about one-fourth the distance from the posterior end, and the other pair at the 

 posterior corners. 



Abdomen not as wide as in the female, the anal laminae a little smaller, but the 

 plumose setae considerably larger. 



2 D 



